3GPP has been studying “ETWS (Earthquake and Tsunami Warning System)” for distributing emergency information (broadcast information) such as earthquake information and tsunami information.
As FIG. 6 shows, a mobile communication system of “EPC (Evolved Packet Core) System” or of “E-UTRAN (Evolved Universal Terrestrial Radio Access Network) System” includes, as a configuration for making notification of such emergency information, a broadcast equipment CBC (Cell Broadcast Center) connected to a CBS provider, a switching center MME (Mobility Management Entity), and a radio base station eNB.
In addition, in such a mobile communication system, a protocol stack between the broadcast equipment CBC and the switching center MME and a protocol stack between the switching center MME and the radio base station eNB are specified as shown in FIG. 7.